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MEMOIRS 

OF THE 

Cx^ENEGIE MUSEUM. 

VOL. IV. NO. 2 



DESCRIPTION OF THREE NEW SPECIES OF CARANGOID 
FISHES FROIM FORMOSA. 

By David Starr Jordan and John Otterbein Snyder. 
* 
The ( -arnegie Museum has lately bought from Dr. Hans Sauter a fine collec- 
tion of fishes, obtained by Dr. Sauter from the port of Takao in Formosa. This 
collection has been placed in the hands of the present writers by Dr. Holland, the 
Director of the Carnegie Museum, for study and identification. 

Among the new species are three, all of the Cltida group of Caranx, which 
seem to be new. One of these constitutes a distinct genus, Ulua. The description 
of these species constitutes the present paper. 

Caranx rastrosus Jordan & Snyder, sp. nov. 
(Plate LI.) 

Head 1^% in length to base of caudal fin ; depth 2y ; depth caudal peduncle 5^ 
in head ; eye 4 ; snout 3 ; interorbital space 3^ ; dorsal VI 1-20 ; anal III-18 ; pores 
in lateral lines about 115. 

Anterior profile rising abruptly to occiput from where the slope to base of 
dorsal is very gradual ; interorbital area high, the sharp median ridge about an eye's 
diameter above orbit ; jaws about equal, the lower projecting slightly ; maxillary 
extending to a vertical through anterior edge of pupil ; width of posterior edge of 
maxillary contained l^ times in suborbital. Minute bristle-like teeth on the jaws, 
vomer, and palatines. Gill-rakers rather long for Caranx, 10-22, those on lower liml) 
of arch short anteriorly, the longest contained 6 times in head. Edges of opercles 
and preopercles membranous. 

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38 MEMOIRS OF THE CARNEGIE MUSEUM 

Body with very small scales ; the throat, breast, a considerable area including 
base and axil of pectoral, and a narrow space extending back from occiput to base of 
dorsal naked ; minute scales on upper edge of opercle and preopercle and also 
on cheek immediately below eye. Lateral line with a long curve above pectoral, the 
curved portion equal to half the length of lateral line ; 14 or 15 small plates on 
tail, each with a low keel and a posterior spine. Base of caudal with 5 pronounced 
lateral keels, the pair on each of the median one oblique and convergent pos- 
teriorly. 

First dorsal with 7 spines, the posterior two separate and very small ; highest 
spine 2^ in head. Anterior part of soft dorsal filamentous, the tip when depressed 
extending beyond base of caudal ; median rays also filamentous, the filamentous 
extending above edge of fin a little over half their length. Anterior rays of anal 
closely united to form a filament which extends to base of caudal when depressed, 
the succeeding rays low. Both soft dorsal and anal with a high sheath of very 
small, thin scales. Ventrals 2^ in head. Pectorals falcate, 2i in the length. Caudal 
lobes equal, 3n;, in the length. 

Color in spirits silvery ; median dorsal region dusky, opercle dusky above, axil 
of pectoral black ; filaments of dorsal and anal black, caudal dusky on edges and 
on posterior border, ventrals tipped with blackish. 

One specimen, the type, from Takao, Formosa, in the (Jarnegie Museum, meas- 
ures 13^ inches in length. There is also a specimen from Cavite, in the Philippines 
in the Museum of Stanford University. 

This species closely resembles Caranx pluvibeus (Quoy and Gaimard) from 
which it differs in having a greater number of gill-rakers (14 on lower limb of first 
arch in Caranx â– plumheus) and a black anal. 

Caranx formosanus Jordan & Snyder, sp. nov. 
(Plate LIT.) 

Head 3i in length to base of caudal ; depth 2 ; depth caudal peduncle 6 in 
head ; eye 4^ ; snout 2i^ ; width interorbital space 3^ ; dorsal VII-23 ; anal 11-19 ; 
jjores in lateral line about 127. 

Dorsal contour of body almost evenly rounded from tip of snout to insertion 
of dorsal, there being but a slight elevation at occiput ; and a small depression 
anterior to nostrils ; interorbital area slightly higher than diameter of eye, the crest 
sharp. Jaws equal ; maxillary extending to a vertical through anterior edge of 
orbit, the width of its posterior edge contained \\ times in the suborbital. Broad 
bands of fine teeth on jaws, vomer, and palatines. Gill-rakers short and strong, 



JORDAN AND SNYDER: CARANGOID FISHES FROM FORMOSA 39 

4-16 on the first arch, those on anterior part of lower limlj very short, the longest 
(near angle of arch) contained 7^ times in head. 

Scales very small ; base and axil of pectoral, breast, and throat naked ; a small 
isolated patch of minute, partly embedded scales anterior to base of pectoral ; cheek 
and upper parts of preopercle and opercle with small scales ; head otherwise naked, 
the unsealed area extending backward to base of spinous dorsal. Lateral line 
broadly curved above pectoral, the curved part including considerably more than 
half of the lateral line ; straight part of the lateral line with small, weak plates, 
those on caiidal peduncle scarcely keeled and without spines. 

Dorsal with 7 spines, the posterior 2 being small and detached ; highest spine 
2-g- in head. Anterior part of soft dorsal elevated but not filamentous, the height 2 
in head ; other rays 4^ in head. Anal similar in shape to dorsal ; height of first 
rays If in head, following rays 4 in head. Caudal lobes equal, 3ro in the length. 
Pectoral falcate, 2f in the length. Ventrals 2^ in the length. 

C'Olor silvery ; a small dusky spot at upper edge of opercle ; axil black ; dorsals, 
anal, and caudal edged with dusky ; ventral and pectoral immaculate. 

Described from the type, an example 11^ inches long from Takao, Formosa, in 
the Carnegie Museum, collected by Dr. Hans Sauter. A similar specimen, differing 
in no particular from the t3^pe, was recorded from Formosa as Caranyus arviatus 
" with opercular spot present ; lobes of dorsal and anal very low " (Jordan & Elver- 
mann, Froc. U. S. Nat. Mus., XXV, p. 338). 

The gill-rakers, few in number and very short, especially on anterior part of 
lower limb, are characteristic of the species. 

ULUA Jordan and Snyder, gen. nov. 

(Type Vlua richardsoni Jordan and Snyder.) 
This genus resembles the subgenus Citula in Camnx, differing in the larger, 
oblique mouth, and especially in the very long gill-rakers, which cause the mouth 
to appear, when opened, as if full of feathers. The name Ulva is Polynesian, being 
applied to the finest food-fish of Hawaii and Samoa, belonging to this group. (V(r- 
anxforsieri Cuv. and Val. 

Ulua RICHARDSONI Jordan <& Snyder, new species. 

(Plate LIIL). 

Head 3^ in length to base of caudal ; depth 2^ ; depth caudal peduncle 6^ in 
head; eye 4x7, ; snout 3; width interorbital space 3^; dorsal VI 1-21 ; anal III- 
10 ; pores in lateral line about 90. 



40 MEMOIRS OF THE CARNEGIE MUSEUM 

Dorsal contour steep from snout to occiput, then I'ising more gently to base ot 
dorsal ; interorbital region high and sharp anteriorly, its edge an eye's diameter from 
orbit. Mouth very large, the maxillary extending to a vertical through center of 
pupil, 2iV in head, the width of its posterior edge contained 1^ times in suborbital 
area ; lower jaw projecting prominently beyond the upper ; no teeth ; gill-rakers 
numerous, 24 -\- 54, and extremely long, the anterior ones projecting upward and 
forward along sides of mouth and base of tongue, small lateral setse giving them a 
distinctly feather-like appearance ; length of longest ones contained 3^ times in head. 
Edges of opercles and preopereles membranous. 

Scales very small, those on lower half of body minute and partly embedded ; 
head, except a small area on upper part of opercle and preopercle, naked ; throat and 
breast naked, the unsealed area extending upward and including base and axil of 
pectoral ; a narrow naked area extending from occiput to base of s^jinous dorsal ; a 
low sheath of scales along bases of soft dorsal and anal. Lateral line with a gentle 
upward curve on anterior half; a conspicuous dorsal branch extending upward to 
occiput and then backward to near origin of spinous dorsal ; posterior part of lateral 
line with about 20 plates which are heaviest on caudal peduncle where a slight keel 
and a blunt spine ai-e developed. Base of caudal with an indistinct keel on each 
side of the median row of plates. 

Height of longest dorsal spine contained 3^ times in head, not reaching origin 
of soft dorsal when depressed, the fin followed by 2 very low free spines ; first 5 or 
6 rays of soft dorsal elongate, giving the anterior part of fin a somewhat falcate 
appearance ; the following rays about equal in height to diameter of eye. Anal 
similar in shape to soft dorsal. Caudal very deeply cleft, the lobes equal, their 
length contained 3^ times in length. Pectoral falcate, 2f in the length. Ventrals 
2f in head. 

Color in spirits bright silvery, somewhat dusky above ; axil of pectoral black ; 
median dorsal area from snout backwards dusky ; dorsals narrowh' edged with 
dusky ; caudal with a dusky margin. 

The above description is taken from the type, a specimen 18 inches long from 
Takao, Formosa, in the Carnegie ^Museum. 

A cotype measuring 9 inches, from the same locality, has the interorbital area 
slightly lower, the soft dorsal decidedly filamentous, the tip extending backward 
to middle of caudal fin, and the pectoral moi'e curved and falcate. Other specimens 
from (Javite, P. I., recorded as Caranx. plumheus (.Jordan and Seale, Bull. Bureau 
Fisherie-s, XXVI, p. 14) do not appear to differ from the Formosan examples. 

The species is named for Mr. Robert Earl Richardson, who first recognized the 
distinctness of the genus. 



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